On Fri, Sep 15, 2023 at 02:23:48PM +0200, Javier Carrasco wrote: > The TPS6598x PD controller provides an active-high hardware reset input > that reinitializes all device settings. If it is not grounded by > design, the driver must be able to de-assert it in order to initialize > the device. > > The PD controller is not ready for registration right after the reset > de-assertion and a delay must be introduced in that case. According to > TI, the delay can reach up to 1000 ms [1], which is in line with the > experimental results obtained with a TPS65987D. > > Add a GPIO descriptor for the reset signal and basic reset management > for initialization and suspend/resume. > > [1] https://e2e.ti.com/support/power-management-group/power-management/ > f/power-management-forum/1269856/tps65987d-tps65987d-reset-de-assert- > to-normal-operation/4809389#4809389 > > Signed-off-by: Javier Carrasco <javier.carrasco@xxxxxxxxxxxxxx> > Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx> > --- > drivers/usb/typec/tipd/core.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c > index 37b56ce75f39..3068ef300073 100644 > --- a/drivers/usb/typec/tipd/core.c > +++ b/drivers/usb/typec/tipd/core.c > @@ -8,6 +8,7 @@ > > #include <linux/i2c.h> > #include <linux/acpi.h> > +#include <linux/gpio/consumer.h> > #include <linux/module.h> > #include <linux/of.h> > #include <linux/power_supply.h> > @@ -43,6 +44,9 @@ > /* TPS_REG_SYSTEM_CONF bits */ > #define TPS_SYSCONF_PORTINFO(c) ((c) & 7) > > +/* reset de-assertion to ready for operation */ > +#define SETUP_MS 1000 > + > enum { > TPS_PORTINFO_SINK, > TPS_PORTINFO_SINK_ACCESSORY, > @@ -86,6 +90,7 @@ struct tps6598x { > struct mutex lock; /* device lock */ > u8 i2c_protocol:1; > > + struct gpio_desc *reset; > struct typec_port *port; > struct typec_partner *partner; > struct usb_pd_identity partner_identity; > @@ -717,6 +722,13 @@ static int tps6598x_probe(struct i2c_client *client) > mutex_init(&tps->lock); > tps->dev = &client->dev; > > + tps->reset = devm_gpiod_get_optional(tps->dev, "reset", GPIOD_OUT_LOW); > + if (IS_ERR(tps->reset)) > + return dev_err_probe(tps->dev, PTR_ERR(tps->reset), > + "failed to get reset GPIO\n"); > + if (tps->reset) > + msleep(SETUP_MS); > + > tps->regmap = devm_regmap_init_i2c(client, &tps6598x_regmap_config); > if (IS_ERR(tps->regmap)) > return PTR_ERR(tps->regmap); > @@ -892,6 +904,9 @@ static void tps6598x_remove(struct i2c_client *client) > tps6598x_disconnect(tps, 0); > typec_unregister_port(tps->port); > usb_role_switch_put(tps->role_sw); > + > + if (tps->reset) > + gpiod_set_value_cansleep(tps->reset, 1); Do you need that "if (tps->reset)" in this case? That function is NULL safe, right? > } > > static int __maybe_unused tps6598x_suspend(struct device *dev) > @@ -902,6 +917,8 @@ static int __maybe_unused tps6598x_suspend(struct device *dev) > if (tps->wakeup) { > disable_irq(client->irq); > enable_irq_wake(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 1); > } > > if (!client->irq) > @@ -918,6 +935,9 @@ static int __maybe_unused tps6598x_resume(struct device *dev) > if (tps->wakeup) { > disable_irq_wake(client->irq); > enable_irq(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 0); > + msleep(SETUP_MS); > } > > if (!client->irq) > > -- > 2.39.2 thanks, -- heikki
